How DLP Technology Works
1. The semiconductor that continues to reinvent projection
At the heart of every DLP® projection system is an optical semiconductor known as the DLP® chip, which was invented by Dr. Larry Hornbeck of Texas Instruments in 1987.
The DLP chip is perhaps the world's most sophisticated light switch. It contains a rectangular array of up to 2 million hinge-mounted microscopic mirrors; each of these micromirrors measures less than one-fifth the width of a human hair.
When a DLP chip is coordinated with a digital video or graphic signal, a light source and a projection lens, its mirrors can reflect a digital image onto a screen or other surface. The DLP chip combined with the advanced electronics that surround it produce stunning images and video that have redefined picture quality.
2. The greyscale image
A DLP chip's micromirrors tilt either towards the light source in a DLP projection system (ON) or away from it (OFF). This creates a light or dark pixel on the projection surface.
The bit-streamed image code entering the semiconductor directs each mirror to switch on and off up to several thousand times per second. When a mirror is switched on more frequently than off, it reflects a light grey pixel; a mirror that's switched off more frequently reflects a darker grey pixel.
In this way, the mirrors in a DLP projection system can reflect pixels in up to 1,024 shades of grey to convert the video or graphic signal entering the DLP chip into a highly detailed greyscale image.
3. Adding colour
The white light generated by the lamp in a DLP projection system passes through a colour filter as it travels to the surface of the DLP chip. This filters the light into a minimum of red, green and blue, from which a single-chip DLP projection system can create at least 16.7 million colours.
With BrilliantColor™ Technology, additional colours are added including cyan, magenta and yellow to expand the colour pallet for even more vibrant colour performance. Some DLP projectors offer solid-state illumination which replaces the traditional white lamp. As a result, the light source emits the necessary colours eliminating the colour filter. In some DLP systems, a 3-chip architecture is used, particularly for high brightness projectors required for large venue applications such as concerts and cinemas. These systems are capable of producing no fewer than 35 trillion colours.
The on and off states of each micromirror are coordinated with these basic building blocks of colour. For example, a mirror responsible for projecting a purple pixel will only reflect red and blue light to the projection surface; those colours are then blended to see the intended hue in a projected image.
4. Applications and configurations
1 CHIP DLP PROJECTION SYSTEM
Many Data projectors and HDTVs using DLP technology rely on a single chip configuration like the one described above.
White light passes through a colour filter, causing red, green, blue and even additional primary colours such as yellow, cyan, magenta and more to be shone in sequence on the surface of the DLP chip. The switching of the mirrors and the proportion of time they are 'on' or 'off' is coordinated according to the colour shining on them. Then the sequential colours blend to create a full-colour image you see on the screen.
3 CHIP DLP PROJECTION SYSTEM
DLP technology-enabled projectors for very high brightness applications such as cinema and large venue displays rely on a 3-chip configuration to produce stunning images, whether moving or still.
In a 3-chip system, the white light generated by the lamp passes through a prism that divides it into red, green and blue. Each DLP chip is identified for each of these three colours; the coloured light that the micromirrors reflect is then combined and passed through the projection lens to form an image.
Regardless of the application or design, Projectors powered by DLP Technology continue to raise the bar on picture quality and video performance. And it all starts with a small imaging chip with millions of tiny mirrors called DLP that make the picture amazing.